Development of a Highly Efficient and Reliable Multi-Tube EGR Cooler

A multi-tube EGR cooler was developed to have high heat exchanger efficiency with high reliability for heavy-duty diesel engine application. Using three-dimensional numerical analyses as well as several laboratory experiments on both a test rig and a diesel engine, the authors determined the most critical factors for developing such an EGR cooler with low production costs.

Technology development focused on achieving a high heat transfer coefficient on the gas side in a tube for increased heat exchanger efficiency and uniform coolant flow distribution in the shell for effective cooling of all tubes in the shell. The tube's inside wall was designed with a spiral configuration both for improved gas flow and heat transfer characteristics. Both the layout of the coolant inlet and outlet on the shell and the arrangement of tubes in the shell were optimized for the best results.